Methacrylic acid:divinylbenzene (MAA:DVB) copolymer for mixed-mode extraction of emerging contaminants from...

The widespread occurrence of emerging contaminants (ECs) in environmental waters presents analytical challenges due to their structural diversity, varied physicochemical properties, and ultra-trace concentrations. Solid-phase extraction (SPE) remains a critical step in sample preparation, but commercial sorbents often lack the versatility needed to simultaneously extract diverse analytes. There is a growing need for cost-effective, customizable sorbents with enhanced selectivity and extraction efficiency.

A novel hypercrosslinked methacrylic acid:divinylbenzene (MAA:DVB) copolymer was developed as a mixed-mode SPE sorbent, combining hydrophobic and weak cation-exchange functionalities. The polymer was synthesized under varying conditions to tune its physical (rigidity, permeability) and chemical (retention capacity) properties, and characterized by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy. A factorial experimental design was used to optimize both polymer synthesis and SPE conditions, such as sample pH, elution solvent, and volumes. The optimum method, coupled with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS), achieved excellent analytical performance: linearity (R² > 0.991), low limits of quantification (50 ng L^-1), and good precision (RSD <15%). The method was successfully applied to real water samples, detecting various ECs, including pharmaceuticals (azithromycin, O-desmethylvenlafaxine, fluconazole, venlafaxine) and pesticides (imidacloprid).

This work demonstrates, for the first time, the application of a lab-made hypercrosslinked MAA:DVB copolymer as a chemically tunable and cost-effective mixed-mode SPE sorbent for broad-spectrum EC extraction. The optimized method provides an efficient alternative to commercial sorbents, significantly enhancing the monitoring of ECs in complex environmental matrices.